Numerical Analysis of the Impact of Intensive Underground Structures on Groundwater Flow in Guangzhou (Canton), China

2014 ◽  
Vol 501-504 ◽  
pp. 1832-1845
Author(s):  
Guanyong Luo ◽  
Hong Cao ◽  
Hong Pan
Keyword(s):  
Groundwater Flow ◽  
Underground Structure ◽  
Hydraulic Head ◽  
Underground Structures ◽  
Groundwater Balance ◽  
Darcy Velocity ◽  
Groundwater Environment ◽  
Structure Density ◽  
The Impact ◽  
The City

The soil over the bedrock in the city of Guangzhou is thin, with a depth of only about 11 m. Under such conditions, excessive exploitation of the underground space is very likely to affect the groundwater environment. In this paper, the impact of intensive underground structures, which act as barriers, on the groundwater flow in Guangzhou is investigated. The emphasis is on the impacts in terms of hydraulic head, Darcy velocity and groundwater balance. The study finds that: (1) Under the current underground structure density, the impact on the hydraulic head is small, and most of the change is in the range of ±0.5 m. (2) The Darcy velocity appears to be more susceptible to being affected by the structures. (3) The barrier effect of the intensive structures increases the overflow at the foot of the hills and reduces the transmissivity of the aquifer.

scholarly journals The impact of heavy object on an underground structure when falling onto the ground surface

2021 ◽  
Vol 17 (4) ◽  
pp. 425-438
Author(s):  
Oleg V. Mkrtychev ◽  
Yury V. Novozhilov ◽  
Anton Yu. Savenkov
Keyword(s):  
Nuclear Power ◽  
Rocket Engine ◽  
Underground Structure ◽  
Ground Surface ◽  
Civil Defense ◽  
Main Task ◽  
Underground Structures ◽  
Building Collapse ◽  
Protective Structures ◽  
The Impact

At the objects of space infrastructure and at nuclear power facilities there are industrial structures, the main task of which is to protect a person, equipment or machinery from emergencies such as, for example, explosions, falling of various objects, fragments. In accordance with the requirements of the Federal Law On the Protection of the Population and Territories from Natural and Technogenic Emergencies, when calculating such structures, all types of loads corresponding to their functional purpose must be taken into account. So, for structures located in the area of a possible accident and the fall of space rockets, it is necessary to calculate for the fall of the destroyed parts of the rocket engine. For nuclear power plant facilities, such accidents occur when containers and other heavy objects fall on the ground, affecting underground structures located in the ground, and for civil defense protective structures built into the basement floors of buildings, it is necessary to consider situations in which the overlying floors of a building collapse when exposed to there is an air shock wave on them. Therefore, this problem is relevant, and in this study, a finite-element method for calculating an underground structure in a non-linear dynamic setting has been developed when a large overall object collides with the ground.

scholarly journals The impact of faults on the hydrogeological conditions in the Roer Valley Rift System: an overview

2003 ◽  
Vol 82 (1) ◽  
pp. 41-54 ◽  
Author(s):  
V.F. Bense ◽  
R.T. Van Balen ◽  
J.J. De Vries
Keyword(s):  
Groundwater Flow ◽  
Hydraulic Properties ◽  
Great Influence ◽  
Hydraulic Head ◽  
Transport Processes ◽  
Rift System ◽  
Near Surface ◽  
Mining Areas ◽  
Vertical Permeability ◽  
The Impact

AbstractThe hydrogeology of the Roer Valley Rift System is strongly influenced by the hydraulic properties of faults. The hydrogeological impact of faults is illustrated by examples from the SE Netherlands and the adjacent lignite mining areas within the Roer Valley Rift System, near Bonn in Germany. Hydraulic head discontinuities over the main faults in the latter area can be up to tens of meters as a result of extremely large groundwater extractions in combination with the relatively low conductivity of the main faults. Within the Netherlands, outside the mining areas, such large groundwater extractions do not take place, and groundwater fluxes are smaller. In this situation natural hydraulic head differences over the main faults are limited to several meters. Hydraulic head profiles over faults provide a first estimate of fault hydraulic properties that can be quantified using simple analytical solutions. The impact of faults on near surface processes is reflected in vegetation patterns and the structure of drainage networks, aquifer structure and hydraulic head patterns. Faults can thus be of great influence on transport processes in the subsurface as well as on water-related phenomena at the surface, and should accordingly be taken into consideration in studies related to water-management, contamination and environmental impact. Faults that have an enhanced vertical permeability are difficult to detect when horizontal groundwater flow is studied, which is probably the main reason why they are rarely described. Though, these faults may form important preferential paths to vertical groundwater flow.

scholarly journals ECOLOGICAL IMPACT ASSESSMENT FOR BUILDING RECONSTRUCTIONS

2021 ◽  
Author(s):  
A.A. Kolpakov ◽  
Keyword(s):  
Impact Assessment ◽  
Negative Impact ◽  
Ecological Impact ◽  
Underground Structures ◽  
Ecological Impact Assessment ◽  
The Impact ◽  
The City

The aim of the work was to analyze the impact on the environment during the reconstruction of buildings. This topic will be of interest to specialists considering the problems of reconstruction of buildings in general. The article assesses the negative impact on the environment of the reconstruction of a children's clinic in the city of Moscow, and also considers the general problems that arise during the reconstruction of buildings and underground structures.

Numerical Simulation on the Influence of the Groundwater Flow Field during Tunnelling

2012 ◽  
Vol 594-597 ◽  
pp. 1230-1233 ◽  
Author(s):  
Xiao Bing Kang ◽  
Xie Wen Hu ◽  
Huai Qian Xie
Keyword(s):  
Numerical Simulation ◽  
Groundwater Flow ◽  
Water Pressure ◽  
High Water ◽  
Tunnel Construction ◽  
Groundwater Environment ◽  
Western Development ◽  
Geological Conditions ◽  
Sphere Of Influence ◽  
The Impact

With the vigorous development of China's economic construction, especially since the western development, needs of traffic tunnel construction are increasing, a large number of tunnels will be built in the mountainous with deeply buried and high water pressure, it is an urgent problem about research on the groundwater environment and the ecological environment in the tunnel site area causes of tunnel construction. The Songpan County Mounigou tunnel located in the high altitude alpine region, regional and environmental geological conditions are complicated, the strata in the tunnel site area is aquifer, and developed faults fractures and fissures, tunnelling will lead to groundwater dewatering and cause the deterioration of the groundwater environment, Then great collapse, burst mud and water gushing will occur during the tunnel construction due to the enrichment of groundwater in tunnel site. Take a research on numerical simulation of groundwater flow in the tunnel site area, the tunnel excavation will form a larger catchment corridor, the impact is bound to the tunnel site hydrogeological conditions in the sphere of influence may appear to lower the groundwater level, seisensui drawdown or part of the dry, provide the basis for tunnel construction.

scholarly journals Effect of anthropogenic heat sources in the shallow subsurface at city-scale

2020 ◽  
Vol 205 ◽  
pp. 07002
Author(s):  
Monika J. Kreitmair ◽  
Nikolas Makasis ◽  
Asal Bidarmaghz ◽  
Ricky L. Terrington ◽  
Gareth J. Farr ◽  
...  
Keyword(s):  
Heat Fluxes ◽  
Anthropogenic Heat ◽  
Transfer Model ◽  
Heat Sources ◽  
Underground Structures ◽  
Shallow Subsurface ◽  
Subsurface Structures ◽  
Systems Quality ◽  
The Impact ◽  
The City

Rapid rates of urbanisation are placing growing demands on cities for accommodation and transportation, with increasing numbers of basements and tunnel networks being built to meet these rising demands. Such subsurface structures constitute continuous heat sources and sinks, particularly if maintained at comfortable temperatures. At the city-scale, there is limited understanding of the effect of heat exchange of underground infrastructures with their environments, in part due to limited availability of long-term underground temperature data. The effects of underground temperature changes due anthropogenic heat fluxes can be significant, impacting ventilation and cooling costs of underground spaces, efficiency of geo-energy systems, quality and quantity of groundwater flow, and the health and maintenance of underground structures. In this paper we explore the impact of anthropogenic subsurface structures on the thermal climate of the shallow subsurface by developing a heat transfer model of the city of Cardiff, UK, utilising a recently developed semi-3D modelling approach.

scholarly journals City-scale groundwater flow and heat transport modeling in the Milan Metropolitan Area

2020 ◽  
Author(s):  
Alberto Previati ◽  
Giovanni Battista Crosta ◽  
Jannis Epting
Keyword(s):  
Groundwater Flow ◽  
Heat Transport ◽  
Metropolitan Area ◽  
Thermal Regime ◽  
Rural Areas ◽  
Anthropogenic Heat ◽  
Heat Sources ◽  
Thermal Potential ◽  
The Impact ◽  
The City

<p>Aquifers beneath big cities are considered a very important resource from an energy and water supply point of view and are increasingly exploited by means of groundwater extraction wells as well as by shallow open- and closed-loop geothermal systems. Moreover, the shallow subsurface of densely populated cities is increasingly hosting underground infrastructures such as tunnels and building foundations. These activities lead to thermal pollution of the shallow urban underground. This phenomenon has already been documented (urban heat island effect) in many cities worldwide with higher ground/groundwater temperatures in the city centers with respect to surrounding rural areas. The local thermal impact of various underground activities has been studied with analytical and local-scale numerical modeling. However, the resulting groundwater thermal regime at the city-scale is yet mostly unexplored.</p><p>In this work the effects of anthropogenic heat sources and subsurface infrastructures in the Milan metropolitan area is presented. To this aim a groundwater head/temperature monitoring network was established in 2016. Groundwater temperatures in the city center are up to 3°C higher with respect to less urbanized areas. A correlation between the urban density and the groundwater thermal regime was observed. In order to evaluate the spatial variability of the groundwater temperatures, a detailed analysis based on a 3D FEM groundwater flow and heat transport numerical model was carried out by means of the commercial code FeFlow. First, the variability of hydraulic and thermal properties as from borehole logs was spatialized into the model by means of 3D geostatistical techniques to account for aquifer heterogeneities. Complex thermal boundary conditions were assigned to the model including the effects of different land cover/sealing materials, building foundations, tunnels, shallow geothermal wells and the canal network. The thermal transport model was calibrated against high-resolution time-lapse groundwater temperature profiles and continuous measurements at fixed depth.</p><p>The modeling of the current thermal regime of the shallow aquifers was essential to understand the hydrogeological and thermal processes that are relevant at the city scale. The numerical results are a valuable tool to assess the impact of specific heat sources as well as of surface/subsurface infrastructures on the overall thermal regime and to test the long-term thermal potential of ground/groundwater heat exchangers under possible urban development scenarios. Thereby, the proposed approach can support the sustainable development of subsurface infrastructures at the city-scale and the management and assessment of the thermal potential of low enthalpy geothermal resources.</p>

scholarly journals Seismic Response Study of Tunnels Running underneath a Subway Station in Parallel

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Fuxue Sun ◽  
Guo-bo Wang ◽  
Xiang-jun Peng ◽  
Zhou-zhou Jin ◽  
Xiao-chun Li ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Underground Structure ◽  
Internal Force ◽  
Underground Structures ◽  
Plane Model ◽  
Metro Station ◽  
Soil Response ◽  
The Impact ◽  
Station Structure ◽  
Range Of Influence

A tunnel passing below a metro station is taken as the object of our study, and a two-dimensional plane model is established to study the effects of their dynamic interaction to seismic excitation. Comparative analysis is used to obtain the influence law between the underground structures and on the soil. The results show that (1) the influence of the underground structure on the soil response is related to structure depth. The range of influence of the station structure on the surface is approximately five times the width of the station, and the surface response is obviously significant within this range. (2) The existence of the tunnel is conducive to reducing the acceleration of the column in the station. It increases the displacement difference between the stations, but the impact on the internal force of the station is not significant. (3) The influence of the station on the dynamic response of the tunnel is consistent with regard to tunnel acceleration, difference in displacement between the top and bottom of the tunnel, and internal force. The presence of the station will reduce the dynamic response of the tunnel.

scholarly journals Impacts of Artificial Underground Reservoir on Groundwater Environment in the Reservoir and Downstream Area

2019 ◽  
Vol 16 (11) ◽  
pp. 1921 ◽  
Author(s):  
Ya Sun ◽  
Shi Guo Xu ◽  
Ping Ping Kang ◽  
Yan Zhao Fu ◽  
Tian Xiang Wang
Keyword(s):  
Groundwater Flow ◽  
Hydrological Cycle ◽  
Dual Function ◽  
Nitrate Accumulation ◽  
Land Use Pattern ◽  
Groundwater Environment ◽  
Underground Reservoir ◽  
Subsurface Dam ◽  
The Impact ◽  
Downstream Area

Artificial underground reservoirs have changed the hydrological cycle from its natural condition. This modification may trigger a series of negative environmental effects both at the local and regional levels. This study investigated the impact of the Wanghe artificial underground reservoir on groundwater flow and quality in the reservoir and its downstream area. Wanghe is a typical artificial underground reservoir scheme in China, which assumes the dual function of fresh-water preservation and control of seawater intrusion. The groundwater flow pattern has changed after the reservoir construction, and the water level in the reservoir rose rapidly. Evaluation of long-term groundwater level fluctuation suggested that the reservoir deprived the downstream aquifer of the runoff, which it received under the natural flow regime. A preliminary isotopic evaluation using 3H was developed to understand the groundwater flow and renewal rates in the study area. The uniform distribution of tritium levels in the reservoir indicated that the stored water was well-mixed in both horizontal and vertical directions. The intervention on groundwater circulation also made differences in groundwater renewal rates between stored and downstream water. Field investigations on groundwater nitrogen pollution showed that the construction of the artificial underground reservoir resulted in nitrate accumulation in the stored water. Agriculturally derived nitrate was the largest contributor, and NO 3 − concentration varied considerably over time due to fertilization and irrigation activities, rainfall, and denitrification. NO 3 − -N distributed homogeneously in the reservoir, which was attributed to the construction of the subsurface dam, land use pattern and artificial groundwater flow.

Study on Civil Engineering with the Comparison and Inspiration of Domestic and Foreign City Underground Space Development

2013 ◽  
Vol 859 ◽  
pp. 213-217
Author(s):  
Xiao Li Dong ◽  
Rui Hua Wang ◽  
Ze Xun Yuan
Keyword(s):  
Regional Planning ◽  
Underground Structure ◽  
Ecological Environment ◽  
Land Resource ◽  
Underground Space ◽  
Underground Structures ◽  
City Population ◽  
Development And Utilization ◽  
City Construction ◽  
The City

With the development of city, city population, regional planning and city ecological environment are facing with more and more tremendous pressure, so the development and utilization of city underground space has become common concern. In recent years, underground structures have been widely applied in the fields of city construction, transportation, defense engineering, water conservancy project etc. Many countries in the world have been the development and utilization of underground space as an important way to intensively implement the land resource and sustainable development of the city. In our country, there is still very great potential of underground space development and utilization of underground structure.

scholarly journals Modelling groundwater recharge in an alluvial aquifer of Somaliland with the groundwater flow model YAGmod

2013 ◽  
Author(s):  
Laura Cattaneo ◽  
Chiara Vassena ◽  
Mauro Giudici ◽  
Bruno Petrucci
Keyword(s):  
Groundwater Flow ◽  
Land Use Planning ◽  
Water Demand ◽  
Management Scenarios ◽  
Groundwater Balance ◽  
The Past ◽  
Dependent Sources ◽  
The Mathematical Model ◽  
The City ◽  
The Town

Since the 1970’s the Ged Deeble (GD) basin is exploited to supply water to the town of Hargeisa (Somaliland, East Africa, 350,000 inhabitants). The goal of this work is to improve the comprehension of the recharge mechanisms, by the simulation of groundwater flow, in order to assess the sustainability of present-day and future exploitation schemes that aim to satisfy the water demand of the city. For this goal, the exploration activities performed in the past were used to reconstruct the geological framework, the basin shape and the mechanisms of recharge and to define the conceptual model. The mathematical model YAGMod, that simulates groundwater steady flow in presence of head-dependent sources and boundary conditions, was applied to quantify the terms of the groundwater balance. Different management scenarios, accompanied by a sensitivity analysis, have been examined to verify if the future water demand of the city could be satisfied and to provide some indications about the land use planning and the management of water resources.

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